The hypervisor debate is a hot topic -- an almost religious debate among some IT pros. Most agree that, up until recently, VMware was the obvious leader in providing advanced virtualization features. However, with the release of Windows Server 2012 Hyper-V,
Step 1: Understand your needs
No matter which product you choose, it's never smart to make that selection without first understanding the needs of your company. After all, the company and its applications are the reason for the data center (and your job). Besides your company's needs, you (and your co-workers in IT) also have your own needs.
In step one, I recommend taking out a pad of paper or using a whiteboard to brainstorm your needs and your company's needs. For example, here's what my list might look like:
My needs for a virtualization hypervisor:
- Reliable support
- Robust ecosystem
Most of my company's needs are the same as the needs that I listed as my personal needs. While that should be the case for you as well, there may be some differences between your needs and your company's. For example, my company might also need a hypervisor to be affordable, have name-brand recognition, or have evidence or case studies showing past implementation success.
Even if your needs and the company's are the same, they might take different directions or they may be weighted far differently. For example, while your interpretation of availability may be that you don't want the hypervisor to crash while you're sleeping, the company's availability needs may be 99.99% application availability. While your scalability requirement may be simply that it isn't a pain to add more servers and VMs, your company may require that the hypervisor support a VM with 1 TB of memory and a VM to host ratio of 300 to 1.
Because it's easy for techies to get excited about speeds and stats when shopping for hypervisors, it's important to only move onto the second step when you fully understand your needs and the needs of the company.
Step 2: Understand the features
I've spent a lot of time creating comparisons between hypervisors, specifically vSphere and Hyper-V. Through those comparisons, I've learned that there are many subtle differences between hypervisors. Often times the biggest difference is in the ecosystem, usability, personal experience and comfort-level.
Now, that's not to say that the hypervisor doesn't matter anymore. While some journalists (and even Microsoft) have tried to make that case, I'm simply not buying it. Why? That's like saying "all automobiles get you from point A to point B, so they're all the same." After all, for most anyone who drives a car, they really care about the car's features and the subtle differences that separate it from the competition.
That being said, what features and benefits should you look for? The answer is the features and benefits that support the needs you listed in step one. If you want flexibility in your hypervisor, then you might like features that can migrate running virtual machines (VMs) from one host to another without downtime (like VMware's vMotion or Microsoft's Live Migration). If you want availability, then you would want features that will automatically restart VMs when a host fails or the operating system crashes.
Make sure you always look for the business benefits of hypervisor features. Don't get caught up in the stats or flashy features if those technical specifications don't matter from a business perspective.
Step 3: Investigate the ecosystem
Many times organizations evaluating a product ignore the ecosystem built (or grown from grass-roots efforts) around the product. Having been an IT manager who evaluated and purchased many software and hardware products, I know it can be easy to get to know salespeople and make purchasing decisions based on their acquaintance and recommendation. It's also easy to go to a vendor-sponsored session, get excited about a product and make a purchase before evaluating the competition.
However, the ecosystem around a product is crucial. I define the ecosystem as many things, which include:
- Availability of product knowledge base articles
- Book, videos and blog content available from third parties
- Training course and certification options
- Third party software tools that can help make your environment more productive
- APIs and application integrations
- The level of participation at local user group meetings
- The number of job openings for skills with that particular product (which shows that other companies are adopting and hiring people with those skills)
- The number of consulting companies that offer services around that product (and have implemented it before at other companies with success)
Talking to other companies to hear about their experiences, good and bad, about the product is also part of investigating the ecosystem. Many times, you can meet these people at a local user group meeting.
Step 4: Compare costs
Businesses are in the business of making money, and they want a solution that has a positive return on investment. However, ROI is tough to calculate for a hypervisor. For example, it's nearly impossible put a number on features that offer greater flexibility.
Still, you can at least compare the hard-dollar costs of the products and what you get at the various price points. Don't always think that you require the highest edition. Also, don't be fooled into thinking that you need the suite; perhaps your remote offices are OK with the free edition of a product. Or perhaps you can wait a few years before jumping to the suite.
No matter the case, don't get fooled into selecting a hypervisor based on cost alone. You need to take into account your needs, the ecosystem around it, and your personal experience with the products.
Step 5: Test for yourself
There is no test like hands-on testing and there is no reading that can replace personal experience. You can't bash one hypervisor or the other until you gain some personal experience with them. Fortunately, you can gain basic experience from your existing desktop or laptop. You can run both VMware vSphere and Microsoft Hyper-V in either VMware Workstation or VMware Fusion to create a nice virtual learning and testing environment.
When it comes time to convince your boss or co-workers, statements that follow words like "in my lab," are very persuasive.
If you are considering replacing your hypervisor or adding a hypervisor to your data center, I hope you will consider using the five steps I covered above to ensure that you are running the best hypervisor for your business.
This was first published in November 2013